Rotermann's salt storage was designed in 1907 and completed in 1908 - a one-storied limestone building with a vaulted basement and massive walls supported by buttresses. The building was erected with its side facing the present Ahtri Street at the site of a former pond. The drawings mere made by Ernst Boustedt (1877-1931), a man of Baltic-German background who had studied civil engineering at the Riga Polytechnic Institute. Originally, the roof of the storage was to be of metal, but was replaced by a wooden structure. The reason for dropping metal structures may have been financial, but also it may have been caused by awareness of the danger of corrosion. In the cellars of the Rotermann's salt storage it is still possible to see (and taste) how salt has penetrated into brick in the course of a century.
The building of the Rotermann's salt storage sharply increased the turnover of Tallinn's salt processing, from 4,500 roubles in 1905 to 551,000 roubles in 1913. By 1911 the export of salt had grown by nearly tenfold, from 23,000 poods to 215,00 poods and the rise continued until World War I. Building of the salt storage had been a good investment.